Today, many people prioritize exercise in their daily routine to stay healthy. As a major sport, basketball attracts a large number of people from high school to the professional level. There are increased requirements in the manufacture of basketballs: first, the process for manufacturing the balls must meet higher environmental protection standards, meaning that harmful solvents, especially benzene-containing organic solvents, are strictly prohibited from being used in the manufacturing process; second, facing fierce competition of labor cost and material cost, leather basketballs must be sold at a more competitive price; third, the market demands a higher quality and performance of the balls, meaning that the synthetic leather bonded to the middle bladder is not allowed to be degummed or edge-warped, and seams existed between the synthetic leather and the rubber string channels are unacceptable.
In the prior art, the basic process for manufacturing a leather basketball comprises the preparing processes of the middle-bladder and the panels. The preparation of the middle bladder further comprises the steps of: rubber mixing, sheeting, die-cutting, thread-wrapping, panel bonding, middle-bladder curing, finished middle-bladder trimming and storing. After bonding the eight panels onto the middle bladder and subsequently curing them, a finished middle bladder can be achieved. However, a large amount of steam and electric energy are consumed during this process, approximately increasing the cost by 0.55 CNY/pcs. Furthermore, the labor cost is increased by 0.2 CNY/pcs due to such a labor-intensive process. Meanwhile, the panels need to be processed by the steps of cutting, logo-printing, edge-skiving, adhesive-coating, heat shaping, air-nozzle mounting, air-inflating, pressure-specifying and panel-bonding. The edge-skiving, adhesive-coating and middle-bladder trimming are manually operated, sharply increasing the labor cost by 1.00 CNY/pcs. Meanwhile, the adhesive coated on the middle bladder further increases the cost by 0.8 CNY/pcs. A certain amount of solvent mixed with the adhesive can easily evaporate to cause air pollution, which is harmful to the operators' health. Consequently, the traditional process is not eco-friendly. The quality of the adhesive, the stability of manually coating the adhesive and trimming the middle bladder can directly determine the stability of the bonding strength between the synthetic leather and the middle bladder. Thus, problems relating to degumming and edge-warping can easily occur during use, seriously affecting the stability and performance of the basketballs. Additionally, the seams existing between the synthetic leather and the rubber string channels cannot be eliminated by such a traditional process. Thus, the basketballs can merely be shipped with an inflated inner bladder, further increasing the transportation cost due to the enlarged volume.
In conclusion, the shortcomings of traditional process for manufacturing a leather basketball are urgent problems that need to be solved for those skilled in this field.